Muscle oxygenation is associated with bilateral strength asymmetry during isokinetic testing in sport teams

Abstract

Objectives. — Muscle oxygenation capacity is a metabolic component that can influence thebilateral strength asymmetry. This study measured the muscle oxygen saturation (SmO2) during aprotocol of high-intensity Results. — Greater average peak torque were found in the DL of the knee extensor muscles (DL:157 ± 28 vs. NDL: 148 ± 25; P = 0.028). Similarly, a SmO2difference (DL: 11.7 ± 10.1 vs. NDL:16.3 ± 13.2; P = 0.044) and critical oxygenation (DL: 20.8 ± 10.1 vs. NDL: 26.3 ± 12; P = 0.049) isassociated with greater bilateral strength asymmetry (r = 0.618 P = 0.01 and r = 0.447 P = 0.03).Also, a greater muscle mass showed an association with a better muscle oxygen extraction.Conclusions. —This study highlights the use of SmO2dynamics as a complement to isokinetictests in order to identify muscle metabolism and muscle imbalances in team sports such asrugby.isokinetic fatigue (FAT) and its relationship with the body composition(BD) at the local level of the vastus lateralis.Methods. — Twenty-two rugby players (age 22.5 ± 4.6 years, weight 89.8 ± 12.6 kg, height176.4 ± 7.8 cm) performed a FAT test to obtain the peak moments (PM) torque of the kneemuscle flexors and extensors. SmO2dynamics was evaluated using a portable NIRS, where mus-cle oxygen consumption, critical oxygenation, muscle oxygen extraction and recovery curveswere obtained. The localized thigh BD was evaluated with dual-energy absorptiometry (DEXA).The tests were evaluated by dominant leg (DL) and non-dominant leg (not DL).